The standard roundup_pow_of_two() and rounddown_pow_of_two() macros use
unsigned long internally, which on 32-bit architectures (like arm32) is
a 32-bit type.
drm_test_buddy_alloc_exceeds_max_order() uses the on a u64 value,
where they silently truncate the 10GB allocation, giving unexpected
success in DRM-CI. (see below the snip).
Fix this by replacing the standard macros with safe 64-bit
power-of-two calculations using ilog2().
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
[23:19:40] [PASSED] drm_test_buddy_alloc_clear
[23:19:40] [PASSED] drm_test_buddy_alloc_range_bias
[23:19:41] [PASSED] drm_test_buddy_fragmentation_performance
[23:19:41] # drm_test_buddy_alloc_exceeds_max_order: EXPECTATION FAILED at drivers/gpu/drm/tests/drm_buddy_test.c:889
[23:19:41] Expected err == -22, but
[23:19:41] err == 0 (0x0)
[23:19:41] ------------[ cut here ]------------
[23:19:41] WARNING: drivers/gpu/drm/drm_buddy.c:405 at drm_buddy_fini+0x114/0x1b8, CPU#0: kunit_try_catch/74
[23:19:41] CPU: 0 UID: 0 PID: 74 Comm: kunit_try_catch Tainted: G N 7.0.0-rc1-gdfb0bcedd08a #1 VOLUNTARY
[23:19:41] Tainted: [N]=TEST
[23:19:41] Hardware name: Generic DT based system
[23:19:41] Call trace:
[23:19:41] unwind_backtrace from show_stack+0x10/0x14
[23:19:41] show_stack from dump_stack_lvl+0x3c/0x4c
[23:19:41] dump_stack_lvl from __warn+0xe8/0x1c4
[23:19:41] __warn from warn_slowpath_fmt+0xa4/0xc0
[23:19:41] warn_slowpath_fmt from drm_buddy_fini+0x114/0x1b8
[23:19:41] drm_buddy_fini from drm_test_buddy_alloc_exceeds_max_order+0x1c8/0x36c
[23:19:41] drm_test_buddy_alloc_exceeds_max_order from kunit_try_run_case+0x78/0x1c8
[23:19:41] kunit_try_run_case from kunit_generic_run_threadfn_adapter+0x1c/0x34
[23:19:41] kunit_generic_run_threadfn_adapter from kthread+0x108/0x134
[23:19:41] kthread from ret_from_fork+0x14/0x28
[23:19:41] Exception stack(0xf0bd5fb0 to 0xf0bd5ff8)
[23:19:41] 5fa0: 00000000 00000000 00000000 00000000
[23:19:41] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[23:19:41] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[23:19:41] ---[ end trace 0000000000000000 ]---
[23:19:41] # drm_test_buddy_alloc_exceeds_max_order: drivers/gpu/drm/drm_buddy.c:406: buddy_fini() root
[23:19:41] ------------[ cut here ]------------
[23:19:41] WARNING: drivers/gpu/drm/drm_buddy.c:414 at drm_buddy_fini+0x1b4/0x1b8, CPU#0: kunit_try_catch/74
[23:19:41] CPU: 0 UID: 0 PID: 74 Comm: kunit_try_catch Tainted: G W N 7.0.0-rc1-gdfb0bcedd08a #1 VOLUNTARY
[23:19:41] Tainted: [W]=WARN, [N]=TEST
[23:19:41] Hardware name: Generic DT based system
[23:19:41] Call trace:
[23:19:41] unwind_backtrace from show_stack+0x10/0x14
[23:19:41] show_stack from dump_stack_lvl+0x3c/0x4c
[23:19:41] dump_stack_lvl from __warn+0xe8/0x1c4
[23:19:41] __warn from warn_slowpath_fmt+0xa4/0xc0
[23:19:41] warn_slowpath_fmt from drm_buddy_fini+0x1b4/0x1b8
[23:19:41] drm_buddy_fini from drm_test_buddy_alloc_exceeds_max_order+0x1c8/0x36c
[23:19:41] drm_test_buddy_alloc_exceeds_max_order from kunit_try_run_case+0x78/0x1c8
[23:19:41] kunit_try_run_case from kunit_generic_run_threadfn_adapter+0x1c/0x34
[23:19:41] kunit_generic_run_threadfn_adapter from kthread+0x108/0x134
[23:19:41] kthread from ret_from_fork+0x14/0x28
[23:19:41] Exception stack(0xf0bd5fb0 to 0xf0bd5ff8)
[23:19:41] 5fa0: 00000000 00000000 00000000 00000000
[23:19:41] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[23:19:41] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[23:19:41] ---[ end trace 0000000000000000 ]---
[23:19:41] [FAILED] drm_test_buddy_alloc_exceeds_max_order
[23:19:41] # drm_buddy: Testing DRM buddy manager, with random_seed=0xacce106c
[23:19:41] # module: drm_buddy_test
[23:19:41] # drm_buddy: pass:8 fail:1 skip:0 total:9
---
drivers/gpu/buddy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/buddy.c b/drivers/gpu/buddy.c
index 52686672e99f..ed4d33a30687 100644
--- a/drivers/gpu/buddy.c
+++ b/drivers/gpu/buddy.c
@@ -1091,7 +1091,7 @@ static int __alloc_contig_try_harder(struct gpu_buddy *mm,
u64 modify_size;
int err;
- modify_size = rounddown_pow_of_two(size);
+ modify_size = 1ULL << ilog2(size);
pages = modify_size >> ilog2(mm->chunk_size);
order = fls(pages) - 1;
if (order == 0)
@@ -1318,7 +1318,7 @@ int gpu_buddy_alloc_blocks(struct gpu_buddy *mm,
/* Roundup the size to power of 2 */
if (flags & GPU_BUDDY_CONTIGUOUS_ALLOCATION) {
- size = roundup_pow_of_two(size);
+ size = 1ULL << (ilog2(size - 1) + 1);
min_block_size = size;
/*
* Normalize the requested size to min_block_size for regular allocations.
--
2.53.0